In launching a boat from a two wheeled trailer, or recovering the boat onto the trailer, the most difficult period of the operation is during the boat's passgae over the end members of the trailer. Various means have been heretofore attempted to facilitate the transition of a boat hull to and from a trailer such as extension tracks, derricks, cables, booms, rollers and combinations of these devices including means to tilt the entire trailer.
Boat trailers have also been built in the past using rollers fixed to the main frame and/or in combination with rollers on the main frame and on sub-frames or cradles pivoted to the main frame. The purpose of these devices has primarily been to facilitate loading and unloading operations, and although many means have been disclosed in the prior art purporting to be solutions to unloading and loading problems, these prior designs have not entirely avoided cumbersome, and/or mechanically inefficient mechanisms.
Another problem in prior designs has been adaptability of the trailer to more than one hull shape. Many designs require permanent mechanical adjustment of some of the supports on the trailer to adapt the hull for each particular boat being carried. Such adjustment involves loosening and tightening threaded fasteners which is an added servicing expense to the dealer and/or an additional cost to the owner. Some designs providing self adjusting support means can only accommodate a limited range of hull shapes.
The present invention provides a solution to previously encountered problems of cumbersome loading and unloading boat trailer hardware in terms of self adjustability, mechanical efficiency, simplicity of operation, reliability, cost of manufacture, ruggedness and ease of maintenance. The self-adjusting cradles of the present invention will adapt to receive a wide range of shapes including flat, round and V-shaped hulls.
It is therefore an object of the present invention to provide a boat trailer which is constructed to facilitate loading and unloading a boat from the trailer.
Another object of the invention is to provide a boat trailer with self-adjusting cradles which adapt to receive and support a wide range of hull shapes.
It is a further object of the invention to provide a boat trailer whose hull engaging rollers are located on self adjusting cradles adapted to equalize the weight of the boat over several support rollers when it is fully loaded onto the trailer.
It is yet a further object of the invention to provide a boat trailer having an end cradle adapted to mechanically assist in loading and unloading operations.